Technical Field
The present disclosure is directed to lifting devices, and more particularly, to portable lifting devices suitable for lifting vehicles and other heavy loads.
Description of the Related Art
Portable lifting devices, such as car jacks, can suffer from stability drawbacks. Such lifting devices are generally designed to lift various types of vehicles or loads in different environments and terrains. As the terrains and loads vary, the heights to which the loads are required to be lifted may vary as well. One particular conventional lifting device 10 shown in FIG. 1, patented under U.S. Pat. No. 4,379,546, includes a nose or lift member 14 that protrudes outward from the lifting device 10 and is adapted to rest against a frame or bumper of a vehicle, a jack base 12, and a vertical member 16, often referred to as a “standard.” As the lift member 14, where the lifting force is applied, moves vertically along the standard 16, the eccentric load application can shift the lifting device 10 forward or to one side, thereby shifting its center of gravity. If the center of gravity approaches a tip over point, the lifting device 10 becomes unstable and susceptible to tip over under even the slightest side load.
Stability problems can be further exacerbated where the surface upon which the device sits is soft, such as on sand or mud, or on uneven surfaces. Conventional lifting devices are typically designed to rest on a flat, firm surface. Accordingly, when lifting on an uneven or soft surface, conventional lifting devices can become particularly unstable, further making some conventional jack devices susceptible to side loads and other loads that may overturn the lifting device during use.